The present invention relates to an improvement on an intercommunication system used in a group teaching or training system.
In order to improve the efficiency of group teaching or training, there have been devised and demonstrated a wide variety of group teaching or training systems in which a data processing and display system is incorporated in a teacher station while a simple answering and display system is incorporated in a number of student stations so that an exchange of information such as questions and answers may be established between a teacher and a plurality of students. If a group teaching or training system incorporated an intercommunication system which established intercommunication not only between the teacher and the students but also between the students themselves, the efficiency of group teaching or training would be further improved. However, in almost all of the conventional group teaching or training systems, the intercommunication may be established only between the teacher and a selected student or students but not among the students themselves. In some group teaching systems which may be used to establish intercommunication among the students, headphones are directly connected to the communication lines so that when too many student stations are included, a drop in signal level results. Therefore the number of student stations is necessarily limited.